<firstimage=”//static.makeuseof.com/wp-content/uploads/2011/04/coolandroidappthumb.jpg”>Smartphones are cool. That’s a given. Not all smartphones are equally cool, however – even when the hardware is the same. The apps that you install on your smartphone can turn it into a non-stop awesome train.

This is particularly true for Android, as Google is very liberal about the apps that can be placed onto the marketplace. You’ll find all manner of unusual apps for your Android phone. Exploration is part of the fun, but there are some very cool Android apps that you can rely on while tailoring your custom collection of cool.

A cooler way to show off your phone’s capabilities is Carrr Matey. The next time you park in a busy mall lot, a concert, or anywhere else you might “lose” your car, just whip out this app. It marks the location of your car, so you can find it later, and does it all with a pirate theme.

One of the coolest emerging technologies focusing on the smartphone is augmented reality. The idea is that you can use your phone’s camera as a window into an augmented world where your surroundings are enhanced by information drawn from the web. Ideally, you could read a restaurant’s menu by taking a photo of it as you pass by, or browse the inventory of a store as you walk by it.

We’re not quite there yet, but there are some cool steps in that direction, and Google Goggles is one of them. You can use this app to take photos of real objects, and you will then be given a relevant search suggestion. Taking a photo of a Starbucks cup, for example, brings up the Starbucks website.

Frankly, search via text is faster and more specific, but this app is plenty awesome, occasionally useful, and provides a brief glimpse of the future.

The idea of adding “wallpaper” to a device using a GUI is decades old now, but it’s not without room for improvement. One frequent complaint is the static nature of wallpaper. Considering the capabilities of modern hardware, why shouldn’t the wallpaper be more dynamic?

Live wallpapers are exactly that. Most Android phones come with some stock live wallpapers, and they’re great. But the ones that will really impress onlookers are on the Android Marketplace. My favorite is Light Grid, a configurable wallpaper based on a grid of multi-colored tiles (or other shapes, if you buy the Pro version) that move and shift randomly and also respond to your touch.

Of course, live wallpapers like Light Grid do tend to consume your phone’s processor. You may experience performance issues or a reduction in battery life. You might want to leave those issues out of your demonstration.

Android phones include the ability to detect magnetic fields – that’s how the compasses found in some apps work. This ability can also be used for other ends, however, such as detecting metal.

There are a few apps out there that allow you to use your Android phone as a metal detector, but the aptly named Metal Detector app is the best free option. You’re not going to find sunken treasures, but you can detect metal within a few inches of the device. It’s great for finding coins in couch cushions and performing weapon inspections on friends. You may want to ask for permission first, though.

Tricorder

Time to geek out! Tricorder isn’t just an app with a clever name. It does exactly what you’d expect – turn your Android into a Tricorder from Star Trek. It looks particularly impressive on Android phones with large displays.

Conclusion

I’m not going to act as if this is some definitive list of cool Android apps. There are over 100,000 apps on the marketplace, so I can’t possibly list all the cool ones here. But I’m sure you, dear readers, can help name a few more in the comments. Which Android apps come under your definition of “cool”?